As is well known to those skilled in this art, neck rings are rotatable assemblies which cooperate with the parison mold to support the upper end of the parison as soon as it is formed and on through the remainder of the molding cycle. Neck rings of the prior art conventionally include a plurality of segments which are held in closed position by such means as a garter type spring which is the only means for holding the neck ring in its closed parison supporting position. Due to the limited holding force of such garter spring arrangements, every time that the parison is formed in the parison mold while in contact with the neck ring assembly, small amounts of molten glass are permitted to enter between the mating surfaces of the neck ring segments resulting in a high rate of wear on the movable and mating components of the neck ring assembly. This, in turn, necessitates frequent replacement of the neck ring assemblies which add substantially to the cost of the molding operation due not only to the cost of the assemblies themselves but to the time necessary for shut-down and replacement.